In various machines it is desirable to provide a slide structure which can move relative to a supporting member in a straight line on a selectively repeatable basis. Although there are various types of slide structures, the slide structure and method of this invention was developed for use on optical comparators and, accordingly, such a device is described herein in conformity with the patent statutes. One prior slide structure for an optical comparator comprises an elongated spindle having an elongated portion slidably received within spaced bores on a stationary member and a threaded portion engaged by a nut member whereby the spindle moves longitudinally with respect to the spaced bores. Such a structure is obviously expensive to produce due to the fit required between the spindle and the bores to obtain accurate straight line movement.
Another prior slide assembly that is used on such a machine tool is a box construction using tapered gibs for removing the shake in the slide system. This produces manufacturing problems because of the need to hold the gibs or scrape them to close tolerances to maintain full contact along their surfaces. This system also must have the tolerance maintained between the hold-downs and the slide to eliminate lateral shaking.